Wireless Power Transmitter With Removable Magnetic Connector Panel For Vehicular Use

ABSTRACT

A power transmitter for wireless power transfer includes a control and communications unit, a vehicular power input regulator, an inverter circuit, at least one coil, a shielding, a housing, and a removable front plate. The housing is configured to house, at least in part, one or more of the control and communications unit, the invertor circuit, the at least one coil, the shielding, or combinations thereof. The removable front plate is configured to mechanically connect to the housing, the removable front plate including at least one magnet, the at least one magnet configured to attract a receiver magnet when a power receiver is proximate to the removable front plate.

TECHNICAL FIELD

The present disclosure generally relates to systems and methods forwireless transfer of electrical power and, more particularly, towireless power transmitters for transmitting power at extendedseparation while maintaining compatibility with magnetic connectors.

BACKGROUND

Wireless power transfer systems are used in a variety of applicationsfor the wireless transfer of electrical energy, electrical powersignals, electromagnetic energy, electrical data signals, among otherknown wirelessly transmittable signals. Such systems often use inductivewireless power transfer, which occurs when magnetic fields created by atransmitting element induce an electric field, and hence, an electriccurrent, in a receiving element. These transmission and receiverelements will often take the form of coiled wires and/or antennas.

Because some wireless power transfer systems are operable and/or mostefficient in the near-field, some transmitters may be limited to havingoperability only at restrictively small gaps between the transmittercoil and the receiver coil. To that end, typical wireless powertransmitters under the Wireless Power Consortium's Qi™ standard may belimited to operability at a maximum coil-to-coil separation gap (whichmay be referred to herein as a “separation gap” or “gap”) of about 3millimeters (mm) to about 5 mm. The separation gap is sometimes known asthe Z-height or Z-distance and is generally measured as the distancebetween the transmitter coil and receiver coil.

As the adoption of wireless power grows, commercial applications arerequiring a power transmitter capable of transferring power to a powerreceiver with a gap greater than 3-5 mm. By way of example, cabinetsand/or counter tops may be more than 3-5 mm thick and as a result,prevent wireless charging through such furniture. As another example,modern mobile devices may be used with cases, grip devices, and/orwallets, among other things, that can obstruct wireless powertransmission to the mobile device and/or create a separation gap thatdisallows operability of wireless power transmission. Legacy wirelesspower transmitter designs further may be incapable of desired commercialapplications (e.g., through object chargers, under table chargers,infrastructure chargers, ruggedized computing device charging, amongother things), due to the limitations in separation gap inherent tolegacy, near-field wireless power transfer systems. Increasing theseparation gap, while keeping satisfactory performance (e.g., thermalperformance, transfer/charging speed, efficiency, etc.) will increasethe number of commercial applications that can utilize wireless power.

SUMMARY

Further, in some applications, devices having wireless power receiversmay include magnetic connectors associated with connection and/oralignment for wireless power transfer. The existence of said magneticconnectors, on wireless power transmitters, require spacing fromtransmitter coil, both for mechanical space considerations and to avoidany magnetics interference during power transfer. Therefore, wirelesspower transmitters having magnetic connectors, capable of connectingwith those associated with receiver systems and/or devices thereof, aredesired.

Additionally, in some examples, tuning or operating frequencycharacteristics of wireless power transmitters/receivers with magneticconnectors may differ from similar transmitters/receivers that do nothave magnetic connectors. Therefore, transmitters that have capabilitiesto change to adapt to the desired receiver may enhance interoperabilityof the transmitter. Further, utilizing the power transmitters withextended transfer distance, as discussed herein, enables such use cases,as the charge envelope can encompass panels that are swappable, toaccommodate receivers with magnetic connectors.

New wireless power transmitters and/or associated base stations aredesired that are capable of delivering wireless power signals to a powerreceiver at a separation gap larger than the about 3 mm to about 5 mmseparation gaps of legacy transmitters. Further, to mitigate any heatingissues that may occur due to an increased power and/or an associatedincrease in separation gap, new systems, methods, and apparatus formitigating such potential heating issues are desired.

In an embodiment, the overall structure of the transmitter is configuredin a way that allows the transmitter to transfer power at an operatingfrequency of about 87 kilohertz (kHz) to about 360 kHz and achieve thesame and/or enhanced relative characteristics (e.g., rate of powertransfer, speed of power transfer, power level, power level management,among other things) of power transfer as legacy transmitters thatoperated in that frequency range. As a result, the separation gap may beincreased from about 3-5 mm to around 15 mm or greater, in comparison tolegacy designs for power transmitters. In an embodiment, a transmitterassembly may be configured with a ferrite core that substantiallysurrounds the transmitter antenna on three sides. The only place thatthe ferrite core does not surround the transmitter antenna is on the top(e.g., in the direction of power transfer) and where the power linesconnect to the transmitter antenna. This overall structure of thetransmitter allows for the combination of power transfercharacteristics, power level characteristics, self-resonant frequencyrestraints, design requirements, adherence to standards bodies' requiredcharacteristics, bill of materials (BOM) and/or form factor constraints,among other things, that allow for power transfer over larger separationgaps.

Transmission of one or more of electrical energy, electrical power,electromagnetic energy or electronic data signals from one of suchcoiled antennas to another, generally, operates at an operatingfrequency and/or an operating frequency range. The operating frequencymay be selected for a variety of reasons, such as, but not limited to,power transfer characteristics, power level characteristics,self-resonant frequency restraints, design requirements, adherence tostandards bodies' required characteristics, bill of materials (BOM)and/or form factor constraints, among other things. It is to be notedthat, “self-resonating frequency,” as known to those having skill in theart, generally refers to the resonant frequency of an inductor due tothe parasitic characteristics of the component.

Additionally, in some embodiments of the present disclosure, a housingis provided that includes two or more airflow openings and/or channelsconfigured for providing airflow to an electronic device when it isbeing powered and/or charged by the wireless power transmittersdisclosed herein. By utilizing the housings disclosed herein, multiplecooling and/or airflow channels may be utilized in mitigating anythermal issues associated with wireless power transmission via thewireless power transmitter. Such thermal issues may include, but are notlimited to including, heating of the wireless power transmitter, heatingof components of the wireless power transmitter, heating of a housingoperatively associated with the wireless power transmitter, heating of amobile device caused from wireless power transmission, heating of amobile device caused by the mobile device, heating of an enclosure of amobile device, heating of materials proximate to the systems, or anycombinations thereof. Such housings may allow for higher power wirelesstransmission, which may allow for faster wireless charging of a mobiledevice, when compared to legacy devices, while also maintaining agreater separation gap and/or Z-distance, in comparison to legacywireless power transmitters.

A vehicle may be a machine that transports people and/or cargo.Exemplary vehicles include automobiles such as cars, trucks, buses, andother land vehicles. Other examples of vehicles may include airplanes,boats, golf carts, small industrial vehicles, farming equipment,construction equipment, nautical vehicles, mixed use vehicles,recreational vehicles, sport vehicles, public transportation vehicles,and trains. Vehicular power sources introduce challenges for designingwireless power transmitters, because the input power is susceptible toone or more of power surges, transients, and electrostatic discharge(ESD), among other things, which may cause damage and/or disfunction inone or both of a power transmitter and the power source system, itself.To that end, a single transient voltage spike has potential to damageand/or disrupt components of the power transmitter's electricalcircuitry. Additionally or alternatively, electrical noise produced by avehicular power source, even that of relatively low energy, can causesignificant interruption to digital communications.

In an embodiment, a vehicle includes a vehicular power input regulatorthat is configured to receive input power and filter the input power toa filtered input power. The vehicular power input regulator includes aninput protection circuit, and a DC/DC voltage converter. An invertercircuit receives the filtered input power and converting the filteredinput power to a power signal. This power signal is provided to a high Zwireless charger. As such, because of the configuration of the vehicularpower input regulator, the vehicular power sources are protected againstpower surges, transients, and electrostatic discharge.

In accordance with one aspect of the disclosure, a power transmitter forwireless power transfer at an operating frequency selected from a rangeof about 87 kilohertz (kHz) to about 360 kHz is disclosed. The powertransmitter includes a control and communications unit, a vehicularpower input regulator, an inverter circuit, at least one coil, ashielding, a housing, and a removable front plate. The vehicular powerinput regulator is configured for receiving input power and filteringthe input power to a filtered input power and includes an inputprotection circuit and a DC/DC voltage converter. The inverter circuitis configured for receiving the filtered input power and converting thefiltered input power to a power signal. The at least one coil isconfigured to transmit the power signal to a power receiver, the atleast one coil formed of wound Litz wire and including at least onelayer, the at least one coil defining, at least, a top face. Theshielding includes a ferrite core and defines a cavity, the cavityconfigured such that the ferrite core substantially surrounds all butthe top face of the coil. The housing is configured to house, at leastin part, one or more of the control and communications unit, theinvertor circuit, the at least one coil, the shielding, or combinationsthereof. The removable front plate is configured to mechanically connectto the housing, the removable front plate including at least one magnet,the at least one magnet configured to attract a receiver magnet when apower receiver is proximate to the removable front plate.

In a refinement, the power transmitter further includes a detectionsensor, the detection sensor configured to determine if the removablefront plate is mechanically connected to the housing.

In a further refinement, the detection sensor is configured to provideinformation of presence of the removable front plate to control powerinput to one or more of the at least one coil.

In yet a further refinement, the at least one coil includes a first coiland a second coil, the first coil being the one of the at least one coilthat is in closest proximity to the at least one magnet, when theremovable plate is mechanically connected to the housing and, if theremovable front plate is mechanically connected to the housing, theinverter circuit is configured to provide the power signal to the firstcoil.

In another further refinement, the power transmitter further includes atuning system, the tuning system configured to selectively tune the atleast one coil to operate at a first operating frequency and a secondoperating frequency and the tuning system is configured to switchbetween the first and second operating frequencies in response topresence of the removable front plate.

In yet a further refinement, the first operating frequency is in a rangeof about 85 kHz to about 205 kHz and the second operating frequency isin a range of about 127 kHz to about 360 kHz.

In another further refinement, the sensor is a physical switch, theswitch operatively associated with the housing and configured togenerate information indicative of presence of the removable frontplate, when the removable front plate contacts the switch.

In another further refinement, the sensor is a magnetic sensorconfigured to detect a particular magnetic field associated with theremovable front plate.

In yet a further refinement, the magnetic sensor is a hall effectsensor.

In another further refinement, the magnetic sensor is configured todetect the at least one magnet of the removable front plate.

In a refinement, the at least one magnet includes a plurality of magnetportions, the plurality of magnet portions including a first northpolarity portion and a first south polarity portion.

In a further refinement, the first north polarity portion is positionedadjacent to the first south polarity portion.

In yet a further refinement, the plurality of magnetic portions furtherincludes a second north polarity portion and the second north polarityportion is positioned adjacent to the first south polarity portion.

In another further refinement, the receiver magnet includes a secondnorth polarity portion and a second south polarity portion, and thefirst north polarity portion is configured to attract the second southpolarity portion and the first south polarity portion is configured toattract the second north polarity portion, when the power receiver isproximate to the removable front plate.

In accordance with another aspect of the disclosure, a base station forwireless power transfer at an operating frequency selected from a rangeof about 87 kilohertz (kHz) to about 360 kHz is disclosed. The basestation includes an interface surface, a control and communicationsunit, a vehicular power input regulator, an inverter circuit, at leastone coil, a shielding, a housing, and a removable front plate. Thevehicular power input regulator is configured for receiving input powerand filtering the input power to a filtered input power and includes aninput protection circuit and a DC/DC voltage converter. The invertercircuit is configured for receiving the filtered input power andconverting the filtered input power to a power signal. The at least onecoil is configured to transmit the power signal to a power receiver, theat least one coil formed of wound Litz wire and including at least onelayer, the at least one coil defining, at least, a top face. Theshielding includes a ferrite core and defines a cavity, the cavityconfigured such that the ferrite core substantially surrounds all butthe top face of the coil. The housing is configured to house, at leastin part, one or more of the control and communications unit, theinvertor circuit, the at least one coil, the shielding, or combinationsthereof. The removable front plate is configured to mechanically connectto the housing, the removable front plate including at least one magnet,the at least one magnet configured to attract a receiver magnet when apower receiver is proximate to the removable front plate.

In a refinement, the input protection circuit includes an overvoltageprotection circuit.

In a refinement, the input protection circuit includes an undervoltageprotection circuit.

In a refinement, the input protection circuit includes an electrostaticdischarge protection circuit.

In a refinement, the input protection circuit includes anelectromagnetic interference mitigation circuit.

In a refinement, the base station further includes a detection sensor,the detection sensor configured to determine if the removable frontplate is mechanically connected to the housing.

These and other aspects and features of the present disclosure will bebetter understood when read in conjunction with the accompanyingdrawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exemplary block diagram of an embodiment of a wirelesspower transfer system, in accordance with an embodiment of the presentdisclosure.

FIG. 2 is an exemplary block diagram for a power transmitter, which maybe used in conjunction with the wireless power transfer system of FIG. 1, in accordance with FIG. 1 and an embodiment of the present disclosure.

FIG. 3 is an exemplary block diagram for components of a control andcommunications system of the power transmitter of FIG. 2 , in accordancewith FIGS. 1-2 and an embodiment of the present disclosure.

FIG. 4 is an exemplary block diagram for components of a sensing systemof the control and communications system of FIG. 3 , in accordance withFIGS. 1-3 and an embodiment of the present disclosure.

FIG. 5 is an exemplary block diagram for components of a powerconditioning system of the power transmitter of FIGS. 1-2 , inaccordance with FIGS. 1-2 and an embodiment of the present disclosure.

FIG. 6 is an exemplary block diagram of another embodiment of a wirelesspower transfer system, in accordance with an embodiment of the presentdisclosure.

FIG. 7 is an exemplary block diagram for another wireless powertransmitter, which may be used in conjunction with the wireless powertransfer system of FIG. 6 , in accordance with FIGS. 1-6 and anembodiment of the present disclosure.

FIG. 8 is an exemplary voltage plot illustrating transient voltagesurges, in accordance with the present disclosure.

FIG. 9A is an exemplary block diagram for a configuration of a vehicularpower input regulator of the power transmitter of FIGS. 1-5 , inaccordance with FIGS. 1-5 and the present disclosure.

FIG. 9B is an exemplary block diagram for another configuration of avehicular power input regulator of the power transmitter of FIGS. 1-5 ,in accordance with FIGS. 1-5 and the present disclosure.

FIG. 9C is an exemplary block diagram for another configuration of avehicular power input regulator of the power transmitter of FIGS. 1-5 ,in accordance with FIGS. 1-5 and the present disclosure.

FIG. 9D is an exemplary block diagram for another configuration of avehicular power input regulator of the power transmitter of FIGS. 1-5 ,in accordance with FIGS. 1-5 and the present disclosure.

FIG. 9E is an exemplary block diagram for another configuration of avehicular power input regulator of the power transmitter of FIGS. 1-5 ,in accordance with FIGS. 1-5 and the present disclosure.

FIG. 10 is an exemplary block diagram illustrating exemplary componentsof an input protection circuit for any of the vehicular power inputregulators of FIGS. 9A-E, in accordance with FIGS. 1-7, 9A-E, and thepresent disclosure.

FIG. 11 is an exemplary electrical schematic diagram of components of apower transmitter of FIGS. 1-7, 9-10 , in accordance with FIGS. 1-7,9-10 and the present disclosure.

FIG. 12 is a perspective view of a shape of a transmitter coil of thepower transmitter of FIGS. 1-7, 9-11 , in accordance with FIGS. 1-7,9-11 and an embodiment of the present disclosure.

FIG. 13 is a cross-section of components of a base station, with whichthe power transmitter 20 is associated, in accordance with FIGS. 1-7,9-12 and the present disclosure.

FIG. 14 is a perspective view of a shielding associated with thetransmitter coil of FIGS. 1-7, 9-13 , in accordance with FIGS. 1-7, 9-13and an embodiment of the present disclosure.

FIG. 15A is a perspective view of the transmitter coil of FIGS. 1-7,9-13 and the shielding of FIGS. 13 and 14 , in accordance with FIGS.1-7, 9-14 and the present disclosure.

FIG. 15B is an exploded perspective view of the transmitter coil ofFIGS. 1-7, 9-13 and the shielding of FIGS. 13 and 14 , in accordancewith FIGS. 1-7, 9-14, 15A and the present disclosure.

FIG. 16A is an exemplary block diagram for an embodiment of the basestation of FIGS. 1-7, 9-15 in accordance with FIGS. 1-7, 9-15 and thepresent disclosure.

FIG. 16B is an exemplary block diagram for another embodiment of thebase station of FIGS. 1-10 in accordance with FIGS. 1-10 and the presentdisclosure.

FIG. 17 is a readout of an actual simulation of magnetic fieldsgenerated by the coils and/or transmitters illustrated in FIGS. 1-7,9-16 and disclosed herein.

FIG. 18A is a perspective view of an exemplary array of transmittercoils for use with the systems, methods, and apparatus of FIGS. 1-7,9-16 , each of the array of transmitter coils constructed, at least inpart, in accordance with coils and/or antennas of FIGS. 1-7, 9-16 , inaccordance with FIGS. 1-7, 9-16 and the present disclosure.

FIG. 18B is a cross sectional side view of the array of transmittercoils of FIG. 18A, in accordance with FIGS. 1-7, 9-16, 18A, and thepresent disclosure.

FIG. 18C is a perspective view of a shielding for the exemplary array oftransmitter coils of FIGS. 18A and 18B, in accordance with FIGS. 1-7,9-16, 18A-B, and the present disclosure.

FIG. 19A is a perspective view of a first example of a housing, withinwhich wireless power transmitters disclosed herein may reside, inaccordance with FIGS. 1-7, 9-16, 18 and the present disclosure.

FIG. 19B is a perspective view of a second example of a housing, withinwhich wireless power transmitters disclosed herein may reside, inaccordance with FIGS. 1-7, 9-16, 18, 19A and the present disclosure.

FIG. 19C is a perspective view of a third example of a housing, withinwhich wireless power transmitters disclosed herein may reside, inaccordance with FIGS. 1-7, 9-16, 18, 19A-B and the present disclosure.

FIG. 20A is a perspective view of a first example removable front platefor the housing of FIG. 19A, in accordance with FIGS. 1-7, 9-16, 18, 19and the present disclosure.

FIG. 20B is a perspective view of a second example removable front platefor the housing of FIG. 19B, in accordance with FIGS. 1-7, 9-16, 18-20Aand the present disclosure.

FIG. 20C is a perspective view of a first example removable front platefor the housing of FIG. 19C, in accordance with FIGS. 1-7, 9-16,18-20A-B and the present disclosure.

FIG. 21A is a top view of a first example configuration for a magneticconnector of the removable front plate of FIGS. 20 , in accordance withFIGS. 1-7, 9-16, 18-20 and the present disclosure. FIG. 21B is a topview of second example configuration for a magnetic connector of theremovable front plate of FIGS. 20 , in accordance with FIGS. 1-7, 9-16,18-21A and the present disclosure.

FIG. 22A is a top view of a first example configuration for a magneticconnector associated with the power receiver and with which the magneticconnector of FIG. 21A is connectable, in accordance with FIGS. 1-7,9-16, 18-21 , and the present disclosure.

FIG. 22B is a top view of a second example configuration for a magneticconnector associated with the power receiver and with which the magneticconnector of FIG. 21B is connectable, in accordance with FIGS. 1-7,9-16, 18-22A and the present disclosure.

FIG. 23A is an example block diagram illustrating functionality of thepower transmitter, housing, and front plate of FIGS. 19A, 20A, inaccordance with FIGS. 1-7, 9-16, 18-22B and the present disclosure.

FIG. 23B is an example block diagram illustrating functionality of thepower transmitter, housing, and front plate of FIGS. 19B, 20B, inaccordance with FIGS. 1-7, 9-16, 18-23A and the present disclosure.

FIG. 23C is is an example block diagram illustrating functionality ofthe power transmitter, housing, and front plate of FIGS. 19C, 20C, inaccordance with FIGS. 1-7, 9-16, 18-23B and the present disclosure.

FIG. 24A is an example block diagram illustrating magnetic connectionproperties of the power transmitter, housing, and front plate of FIGS.19A, 20A, 23A, in accordance with FIGS. 1-7, 9-16, 18-23C and thepresent disclosure.

FIG. 24B is an example block diagram illustrating magnetic connectionproperties of the power transmitter, housing, and front plate of FIGS.19B, 20B, 23B, in accordance with FIGS. 1-7, 9-16, 18-24A and thepresent disclosure.

FIG. 24C is an example block diagram illustrating magnetic connectionproperties of the power transmitter, housing, and front plate of FIGS.19C, 20C, 23C, in accordance with FIGS. 1-7, 9-16, 18-24B and thepresent disclosure.

FIG. 25A is an example block diagram illustrating coil connection andcontrol in the power transmitter, in accordance with FIGS. 1-7, 9-16,18-24C and the present disclosure.

FIG. 25B is another example block diagram illustrating coil connectionand control in the power transmitter, in accordance with FIGS. 1-7,9-16, 18-25A and the present disclosure.

FIG. 26 is an example block diagram illustrating tuning functions of apower transmitter with removable front plate, in accordance with FIGS.1-7, 9-16, 18-25 and the present disclosure.

While the following detailed description will be given with respect tocertain illustrative embodiments, it should be understood that thedrawings are not necessarily to scale and the disclosed embodiments aresometimes illustrated diagrammatically and in partial views. Inaddition, in certain instances, details which are not necessary for anunderstanding of the disclosed subject matter or which render otherdetails too difficult to perceive may have been omitted. It shouldtherefore be understood that this disclosure is not limited to theparticular embodiments disclosed and illustrated herein, but rather to afair reading of the entire disclosure and claims, as well as anyequivalents thereto. Additional, different, or fewer components andmethods may be included in the systems and methods.

DETAILED DESCRIPTION

In the following description, numerous specific details are set forth byway of examples in order to provide a thorough understanding of therelevant teachings. However, it should be apparent to those skilled inthe art that the present teachings may be practiced without suchdetails. In other instances, well known methods, procedures, components,and/or circuitry have been described at a relatively high-level, withoutdetail, in order to avoid unnecessarily obscuring aspects of the presentteachings.

Referring now to the drawings and with specific reference to FIG. 1 , awireless power transfer system 10A is illustrated. The wireless powertransfer system 10A provides for the wireless transmission of electricalsignals, such as, but not limited to, electrical energy, electricalpower signals, and electromagnetic energy. Additionally, the wirelesspower transfer system 10A may provide for wireless transmission ofelectronically transmittable data (“electronic data”) independent ofand/or associated with the aforementioned electrical signals.Specifically, the wireless power transfer system 10A provides for thewireless transmission of electrical signals via near field magneticcoupling. As shown in the embodiment of FIG. 1 , the wireless powertransfer system 10 includes a power transmitter 20A and a power receiver30. The power receiver 30 is configured to receive electrical energy,electrical power, electromagnetic energy, and/or electronic data from,at least, the power transmitter 20A.

As illustrated, the power transmitter 20A and power receiver 30 may beconfigured to transmit electrical energy, via transmitter antenna 21 andreceiver antenna 31, electrical power, electromagnetic energy, and/orelectronically transmittable data across, at least, a separationdistance or gap 17. A separation distance or gap, such as the gap 17, inthe context of a wireless power transfer system, such as the system 10,does not include a physical connection, such as a wired connection.There may be intermediary objects located in a separation distance orgap, such as the gap 17, such as, but not limited to, air, a countertop, a casing for an electronic device, a grip device for a mobiledevice, a plastic filament, an insulator, a mechanical wall, among otherthings; however, there is no physical, electrical connection at such aseparation distance or gap.

The combination of the power transmitter 20A and the power receiver 30create an electrical connection without the need for a physicalconnection. “Electrical connection,” as defined herein, refers to anyfacilitation of a transfer of an electrical current, voltage, and/orpower from a first location, device, component, and/or source to asecond location, device, component, and/or destination. An “electricalconnection” may be a physical connection, such as, but not limited to, awire, a trace, a via, among other physical electrical connections,connecting a first location, device, component, and/or source to asecond location, device, component, and/or destination. Additionally oralternatively, an “electrical connection” may be a wireless electricalconnection, such as, but not limited to, magnetic, electromagnetic,resonant, and/or inductive field, among other wireless electricalconnections, connecting a first location, device, component, and/orsource to a second location, device, component, and/or destination.

Alternatively, the gap 17 may be referenced as a “Z-Distance,” because,if one considers an antenna 21, 31 to be disposed substantially along acommon X-Y plane, then the distance separating the antennas 21, 31 isthe gap in a “Z” or “depth” direction. However, flexible and/ornon-planar coils are certainly contemplated by embodiments of thepresent disclosure and, thus, it is contemplated that the gap 17 may notbe uniform, across an envelope of connection distances between theantennas 21, 31. It is contemplated that various tunings,configurations, and/or other parameters may alter the possible maximumdistance of the gap 17, such that electrical transmission from the powertransmitter 20 to the power receiver 30 remains possible.

The wireless power transfer system 10A operates when the powertransmitter 20 and the power receiver 30 are coupled. As defined herein,the terms “couples,” “coupled,” and “coupling” generally refers tomagnetic field coupling, which occurs when the energy of a transmitterand/or any components thereof and the energy of a receiver and/or anycomponents thereof are coupled to each other through a magnetic field.Coupling of the power transmitter 20 and the power receiver 30, in thesystem 10A, may be represented by a resonant coupling coefficient of thesystem 10A and, for the purposes of wireless power transfer, thecoupling coefficient for the system 10A may be in the range of about0.01 and 0.9.

The power transmitter 20A may be operatively associated with a basestation 11. The base station 11 may be a device, such as a charger, thatis able to provide near-field inductive power, via the power transmitter20, to a power receiver. In some examples, the base station 11 may beconfigured to provide such near-field inductive power as specified inthe Qi™ Wireless Power Transfer System, Power Class 0 Specification. Insome such examples, the base station 11 may carry a logo to visuallyindicate to a user that the base station 11 complies with the Qi™Wireless Power Transfer System, Power Class 0 Specification.

The power transmitter 20A may receive power from an input power source12. The base station 11 may be any electrically operated device, circuitboard, electronic assembly, dedicated charging device, or any othercontemplated electronic device. Example base stations 11, with which thepower transmitter 20A may be associated therewith, include, but are notlimited to including, a device that includes an integrated circuit,cases for wearable electronic devices, receptacles for electronicdevices, a portable computing device, clothing configured withelectronics, storage medium for electronic devices, charging apparatusfor one or multiple electronic devices, dedicated electrical chargingdevices, activity or sport related equipment, goods, and/or datacollection devices, among other contemplated electronic devices.

The input power source 12 may be or may include one or more electricalstorage devices, such as an electrochemical cell, a battery pack, and/ora capacitor, among other storage devices. Additionally or alternatively,the input power source 12 may be any electrical input source (e.g., anyalternating current (AC) or direct current (DC) delivery port) and mayinclude connection apparatus from said electrical input source to thewireless transmission system 20A (e.g., transformers, regulators,conductive conduits, traces, wires, or equipment, goods, computer,camera, mobile phone, and/or other electrical device connection portsand/or adaptors, such as but not limited to USB or lighting ports and/oradaptors, among other contemplated electrical components).

Electrical energy received by the power transmitter 20A is then used forat least two purposes: providing electrical power to internal componentsof the power transmitter 20 and providing electrical power to thetransmitter coil 21. The transmitter coil 21 is configured to wirelesslytransmit the electrical signals conditioned and modified for wirelesstransmission by the power transmitter 20 via near-field magneticcoupling (NFMC). Near-field magnetic coupling enables the transfer ofelectrical energy, electrical power, electromagnetic energy, and/orelectronically transmissible data wirelessly through magnetic inductionbetween the transmitter coil 21 and a receiving coil 31 of, orassociated with, the power receiver 30. Near-field magnetic coupling mayenable “inductive coupling,” which, as defined herein, is a wirelesspower transmission technique that utilizes an alternatingelectromagnetic field to transfer electrical energy between two or moreantennas/coils. Such inductive coupling is the near field wirelesstransmission of electrical energy between two magnetically coupled coilsthat are tuned to resonate at a similar frequency. Further, suchnear-field magnetic coupling may provide connection via “mutualinductance,” which, as defined herein is the production of anelectromotive force in a circuit by a change in current in at least onecircuit magnetically coupled to the first.

In one or more embodiments, the inductor coils of either the transmittercoil 21 or the receiver coil 31 are strategically positioned tofacilitate reception and/or transmission of wirelessly transferredelectrical energy, power, electromagnetic energy and/or data throughnear field magnetic induction. Antenna operating frequencies maycomprise all operating frequency ranges, examples of which may include,but are not limited to, about 87 kHz to about 205 kHz (Qi™ interfacestandard). The operating frequencies of the coils 21, 31 may beoperating frequencies designated by the International TelecommunicationsUnion (ITU) in the Industrial, Scientific, and Medical (ISM) frequencybands.

As known to those skilled in the art, a “resonant frequency” or“resonant frequency band” refers to a frequency or frequencies whereinamplitude response of the antenna is at a relative maximum, or,additionally or alternatively, the frequency or frequency band where thecapacitive reactance has a magnitude substantially similar to themagnitude of the inductive reactance. In one or more embodiments thetransmitting antenna resonant frequency band extends from about 87 kHzto about 205 kHz. In one or more embodiments the inductor coil of thereceiver coil 31 is configured to resonate at a receiving antennaresonant frequency or within a receiving antenna resonant frequencyband.

In some examples, the transmitting coil and the receiving coil of thepresent disclosure may be configured to transmit and/or receiveelectrical power at a baseline power profile having a magnitude up toabout 5 watts (W). In some other examples, the transmitting coil and thereceiving coil of the present disclosure may be configured to transmitand/or receive electrical power at an extended power profile, supportingtransfer of up to 15 W of power.

The power receiver 30 is configured to acquire near-field inductivepower from the power transmitter 20A. In some examples, the powerreceiver 30 is a subsystem of an electronic device 14. The electronicdevice 14 may be any device that is able to consume near field inductivepower as specified in the Qi™ Wireless Power Transfer System, PowerClass 0 Specification. In some such examples, the electronic device 14may carry a logo to visually indicate to a user that the electronicdevice 14 complies with the Specification.

The electronic device 14 may be any device that requires electricalpower for any function and/or for power storage (e.g., via a batteryand/or capacitor). Additionally or alternatively, the electronic device14 may be any device capable of receipt of electronically transmissibledata. For example, the device may be, but is not limited to being, ahandheld computing device, a mobile device, a portable appliance, anintegrated circuit, an identifiable tag, a kitchen utility device, anautomotive device, an electronic tool, an electric vehicle, a gameconsole, a robotic device, a wearable electronic device (e.g., anelectronic watch, electronically modified glasses, altered-reality (AR)glasses, virtual reality (VR) glasses, among other things), a portablescanning device, a portable identifying device, a sporting good, anembedded sensor, an Internet of Things (IoT) sensor, IoT enabledclothing, IoT enabled recreational equipment, industrial equipment,medical equipment, a medical device, a tablet computing device, aportable control device, a remote controller for an electronic device, agaming controller, among other things.

For the purposes of illustrating the features and characteristics of thedisclosed embodiments, arrow-ended lines are utilized to illustratetransferrable and/or communicative signals and various patterns are usedto illustrate electrical signals that are intended for powertransmission and electrical signals that are intended for thetransmission of data and/or control instructions. Solid lines indicatesignal transmission of electrical energy, electrical power signals,and/or electromagnetic energy over a physical and/or wireless electricalconnection, in the form of power signals that are, ultimately, utilizedin wireless power transmission from the power transmitter 20A to thepower receiver 30. Further, dotted lines are utilized to illustrateelectronically transmittable data signals, which ultimately may bewirelessly transmitted from the power transmitter 20A to the powerreceiver 30.

Turning now to FIG. 2 , the wireless power transfer system 10A isillustrated as a block diagram including example sub-systems of thepower transmitter 20A. The power transmitter 20A may include, at least,a power conditioning system 40, a control and communications system 26,a sensing system 50, and the transmission coil 21. In some examples, thepower transmitter 20 includes and/or is contained within a housing 100,examples of which are discussed in detail below, with reference to FIGS.19-24 .

A first portion of the electrical energy input from the input powersource 12 is configured to electrically power components of the powertransmitter 20A such as, but not limited to, the control andcommunications system 26. A second portion of the electrical energyinput from the input power source 12 is conditioned and/or modified forwireless power transmission, to the power receiver 30, via thetransmission coil 21. Accordingly, the second portion of the inputenergy is modified and/or conditioned by the power conditioning system40. While not illustrated, it is certainly contemplated that one or bothof the first and second portions of the input electrical energy may bemodified, conditioned, altered, and/or otherwise changed prior toreceipt by the power conditioning system 40 and/or transmission controlsystem 26, by further contemplated subsystems (e.g., a voltageregulator, a current regulator, switching systems, fault systems, safetyregulators, among other things).

The control and communications system 26, generally, comprises digitallogic portions of the power transmitter 20A. The control andcommunications system 26 receives and decodes messages from the powerreceiver 30, executes the relevant power control algorithms andprotocols, and drives the frequency of the AC waveform to control thepower transfer. As discussed in greater detail below, the control andcommunications system 26 also interfaces with other subsystems of thepower transmitter 20A. For example, the control and communicationssystem 26 may interface with other elements of the power transmitter 20for user interface purposes.

Referring now to FIG. 3 , with continued reference to FIGS. 1 and 2 ,subcomponents and/or systems of the control and communications system 26are illustrated. The control and communications system 26 may include atransmission controller 28, a communications system 29, a driver 48, anda memory 27.

The transmission controller 28 may be any electronic controller orcomputing system that includes, at least, a processor which performsoperations, executes control algorithms, stores data, retrieves data,gathers data, controls and/or provides communication with othercomponents and/or subsystems associated with the power transmitter 20,and/or performs any other computing or controlling task desired. Thetransmission controller 28 may be a single controller or may includemore than one controller disposed to control various functions and/orfeatures of the power transmitter 20A. Functionality of the transmissioncontroller 28 may be implemented in hardware and/or software and mayrely on one or more data maps relating to the operation of the powertransmitter 20A. To that end, the transmission controller 28 may beoperatively associated with the memory 27. The memory may include one ormore of internal memory, external memory, and/or remote memory (e.g., adatabase and/or server operatively connected to the transmissioncontroller 28 via a network, such as, but not limited to, the Internet).The internal memory and/or external memory may include, but are notlimited to including, one or more of a read only memory (ROM), includingprogrammable read-only memory (PROM), erasable programmable read-onlymemory (EPROM or sometimes but rarely labelled EROM), electricallyerasable programmable read-only memory (EEPROM), random access memory(RAM), including dynamic RAM (DRAM), static RAM (SRAM), synchronousdynamic RAM (SDRAM), single data rate synchronous dynamic RAM (SDRSDRAM), double data rate synchronous dynamic RAM (DDR SDRAM, DDR2, DDR3,DDR4), and graphics double data rate synchronous dynamic RAM (GDDRSDRAM, GDDR2, GDDR3, GDDR4, GDDR5, a flash memory, a portable memory,and the like. Such memory media are examples of nontransitory machinereadable and/or computer readable memory media.

While particular elements of the control and communications system 26are illustrated as independent components and/or circuits (e.g., thedriver 48, the memory 27, the communications system 29, among othercontemplated elements) of the control and communications system 26, suchcomponents may be integrated with the transmission controller 28. Insome examples, the transmission controller 28 may be an integratedcircuit configured to include functional elements of one or both of thetransmission controller 28 and the power transmitter 20A, generally.

As illustrated, the transmission controller 28 is in operativeassociation, for the purposes of data transmission, receipt, and/orcommunication, with, at least, the memory 27, the communications system29, the power conditioning system 40, the driver 48, and the sensingsystem 50. The driver 48 may be implemented to control, at least inpart, the operation of the power conditioning system 40. In someexamples, the driver 48 may receive instructions from the transmissioncontroller 28 to generate and/or output a generated pulse widthmodulation (PWM) signal to the power conditioning system 40. In somesuch examples, the PWM signal may be configured to drive the powerconditioning system 40 to output electrical power as an alternatingcurrent signal, having an operating frequency defined by the PWM signal.

The sensing system 50 may include one or more sensors, wherein eachsensor may be operatively associated with one or more components of thepower transmitter 20A and configured to provide information and/or data.The term “sensor” is used in its broadest interpretation to define oneor more components operatively associated with the power transmitter 20Athat operate to sense functions, conditions, electrical characteristics,operations, and/or operating characteristics of one or more of the powertransmitter 20A, the power receiver 30, the input power source 12, thebase station 11, the transmission coil 21, the receiver coil 31, alongwith any other components and/or subcomponents thereof.

As illustrated in the embodiment of FIG. 4 , the sensing system 50 mayinclude, but is not limited to including, a thermal sensing system 52,an object sensing system 54, a receiver sensing system 56, electricalsensor(s) 57 and/or any other sensor(s) 58. Within these systems, theremay exist even more specific optional additional or alternative sensingsystems addressing particular sensing aspects required by anapplication, such as, but not limited to: a condition-based maintenancesensing system, a performance optimization sensing system, astate-of-charge sensing system, a temperature management sensing system,a component heating sensing system, an IoT sensing system, an energyand/or power management sensing system, an impact detection sensingsystem, an electrical status sensing system, a speed detection sensingsystem, a device health sensing system, among others. The object sensingsystem 54, may be a foreign object detection (FOD) system.

Each of the thermal sensing system 52, the object sensing system 54, thereceiver sensing system 56 and/or the other sensor(s) 58, including theoptional additional or alternative systems, are operatively and/orcommunicatively connected to the transmission controller 28. The thermalsensing system 52 is configured to monitor ambient and/or componenttemperatures within the power transmitter 20A or other elements nearbythe power transmitter 20A. The thermal sensing system 52 may beconfigured to detect a temperature within the power transmitter 20A and,if the detected temperature exceeds a threshold temperature, thetransmission controller 28 prevents the power transmitter 20A fromoperating. Such a threshold temperature may be configured for safetyconsiderations, operational considerations, efficiency considerations,and/or any combinations thereof. In a non-limiting example, if, viainput from the thermal sensing system 52, the transmission controller 28determines that the temperature within the power transmitter 20A hasincreased from an acceptable operating temperature to an undesiredoperating temperature (e.g., in a non-limiting example, the internaltemperature increasing from about 20° Celsius (C) to about 50° C., thetransmission controller 28 prevents the operation of the powertransmitter 20A and/or reduces levels of power output from the powertransmitter 20A. In some non-limiting examples, the thermal sensingsystem 52 may include one or more of a thermocouple, a thermistor, anegative temperature coefficient (NTC) resistor, a resistancetemperature detector (RTD), and/or any combinations thereof.

As depicted in FIG. 4 , the transmission sensing system 50 may includethe object sensing system 54. The object sensing system 54 may beconfigured to detect presence of unwanted objects in contact with orproximate to the power transmitter 20A. In some examples, the objectsensing system 54 is configured to detect the presence of an undesiredobject. In some such examples, if the transmission controller 28, viainformation provided by the object sensing system 54, detects thepresence of an undesired object, then the transmission controller 28prevents or otherwise modifies operation of the power transmitter 20A.In some examples, the object sensing system 54 utilizes an impedancechange detection scheme, in which the transmission controller 28analyzes a change in electrical impedance observed by the transmissioncoil 21 against a known, acceptable electrical impedance value or rangeof electrical impedance values. Additionally or alternatively, in someexamples the object sensing system 54 may determine if a foreign objectis present by measuring power output associated with the powertransmitter 20A and determining power input associated with a receiverassociated with the power transmitter 20A. In such examples, the objectsensing system 54 may calculate a difference between the powerassociated with the power transmitter 20A and the power associated withthe receiver and determine if the difference indicates a loss,consistent with a foreign object not designated for wireless powertransmission.

Additionally or alternatively, the object sensing system 54 may utilizea quality factor (Q) change detection scheme, in which the transmissioncontroller 28 analyzes a change from a known quality factor value orrange of quality factor values of the object being detected, such as thereceiver coil 31. The “quality factor” or “Q” of an inductor can bedefined as (frequency (Hz)×inductance (H))/resistance (ohms), wherefrequency is the operational frequency of the circuit, inductance is theinductance output of the inductor and resistance is the combination ofthe radiative and reactive resistances that are internal to theinductor. “Quality factor,” as defined herein, is generally accepted asan index (figure of measure) that measures the efficiency of anapparatus like an antenna, a circuit, or a resonator. In some examples,the object sensing system 54 may include one or more of an opticalsensor, an electro-optical sensor, a Hall effect sensor, a proximitysensor, and/or any combinations thereof.

The receiver sensing system 56 is any sensor, circuit, and/orcombinations thereof configured to detect presence of any wirelessreceiving system that may be couplable with the power transmitter 20A.In some examples, if the presence of any such wireless receiving systemis detected, wireless transmission of electrical energy, electricalpower, electromagnetic energy, and/or data by the power transmitter tosaid wireless receiving system is enabled. In some examples, if thepresence of a wireless receiver system is not detected, wirelesstransmission of electrical energy, electrical power, electromagneticenergy, and/or data is prevented from occurring. Accordingly, thereceiver sensing system 56 may include one or more sensors and/or may beoperatively associated with one or more sensors that are configured toanalyze electrical characteristics within an environment of or proximateto the power transmitter 20A and, based on the electricalcharacteristics, determine presence of a power receiver 30.

The electrical sensor(s) 57 may include any sensors configured fordetecting and/or measuring any current, voltage, and/or power within thepower transmitter 20A. Information provided by the electrical sensor(s)57, to the transmission controller 28, may be utilized independentlyand/or in conjunction with any information provided to the transmissioncontroller 28 by one or more of the thermal sensing system 52, theobject sensing system 54, the receiver sensing system 56, the othersensor(s) 58, and any combinations thereof.

Referring now to FIG. 5 , and with continued reference to FIGS. 1-4 , ablock diagram illustrating an embodiment of the power conditioningsystem 40 is illustrated. At the power conditioning system 40,electrical power is received, generally, as a DC power source, via theinput power source 12 itself or an intervening power converter,converting an AC source to a DC source (not shown). A voltage regulator46 receives the electrical power from the input power source 12 and isconfigured to provide electrical power for transmission by the coil 21and provide electrical power for powering components of the powertransmitter 20A. Accordingly, the voltage regulator 46 is configured toconvert the received electrical power into at least two electrical powersignals, each at a proper voltage for operation of the respectivedownstream components: a first electrical power signal to electricallypower any components of the power transmitter 20A and a second portionconditioned and modified for wireless transmission to the wirelessreceiver system 30. As illustrated in FIG. 3 , such a first portion istransmitted to, at least, the sensing system 50, the transmissioncontroller 28, and the communications system 29; however, the firstportion is not limited to transmission to just these components and canbe transmitted to any electrical components of the power transmitter20A.

The second portion of the electrical power is provided to an amplifier42 of the power conditioning system 40, which is configured to conditionthe electrical power for wireless transmission by the coil 21. Theamplifier may function as an inverter, which receives an input DC powersignal from the voltage regulator 46 and generates an AC as output,based, at least in part, on PWM input from the transmission controlsystem 26. The amplifier 42 may be or include, for example, a powerstage inverter. The use of the amplifier 42 within the powerconditioning system 40 and, in turn, the power transmitter 20 enableswireless transmission of electrical signals having much greateramplitudes than if transmitted without such an amplifier. For example,the addition of the amplifier 42 may enable the wireless transmissionsystem 20A to transmit electrical energy as an electrical power signalhaving electrical power from about 10 milliwatts (mW) to about 60 W.

Turning now to FIG. 6 , another wireless power transfer system 10B isillustrated. The wireless power transfer system 10B includes most of thesame elements as the wireless power transfer system 10A and, thus, thebase station transmission antenna 21, the receiver antenna 31, the powerreceiver 30, the load 16, the electronic device 14, and the input powersource 12 are functionally equivalent to those of FIG. 1 and share thesame written description as those above, with reference to FIGS. 1-5 .In contrast with the wireless power transfer system 10A, the input powersource 12 in the wireless power transfer system 10B is operativelyassociated with a vehicle 15. While it certainly is possible that thesystem 10A of FIG. 1 and/or components thereof may be operativelyassociated with a vehicle, it is particularly illustrated in FIG. 5 forthe purposes of this exemplary embodiment of the disclosure.Additionally, the system 10B includes a power transmitter 20B, whichshares many like elements to the power transmitter 20A, as discussedbelow. The power transmitter 20B may comprise or be operativelyassociated with a base station 11B.

The vehicle 15 may be a machine that transports people and/or cargo.Exemplary vehicles include automobiles such as cars, trucks, buses, andother land vehicles. Other examples of vehicles may include airplanes,boats, golf carts, small industrial vehicles, farming equipment,construction equipment, nautical vehicles, mixed use vehicles,recreational vehicles, sport vehicles, public transportation vehicles,and trains. Thus, the input power source 12 may be or may include one ormore vehicular electrical inputs, vehicular batteries, vehicular powerrails, electrical storage devices, such as an electrochemical cell, abattery pack, and/or a capacitor, among other storage devices.Additionally or alternatively, the input power source 12 may be anyelectrical input source (e.g., any alternating current (AC) or directcurrent (DC) delivery port) and may include connection apparatus fromsaid electrical input source to the wireless transmission system 20B(e.g., transformers, regulators, rectifiers, conductive conduits,traces, wires, or equipment, goods, computer, camera, mobile phone,and/or other electrical device connection ports and/or adaptors, such asbut not limited to USB or lighting ports and/or adaptors, among othercontemplated electrical components).

FIG. 7 illustrates the power transmitter 20B. The power transmitter 20Bincludes most of the same elements as the power transmitter 20A and,thus, the control and communications system 26, the power conditioningsystem 40, the transmitter coil 21, the sensing system 50, and thehousing 100 share the same written description as those above, withreference to FIGS. 1-5 . In contrast with the wireless power transfersystem 20A, the power transmitter 20B includes a vehicular power inputregulator 90. The vehicular power input regulator 90 is configured toreceive and regulate the power input from the input power source 12 togenerate a filtered input power to transmit to the power conditioningsystem 40.

When the input power source 12 is a vehicular power source, the inputpower received by the vehicular power input regulator 90 is susceptibleto one or more of power surges, transients, and electrostatic discharge(ESD), among other things. To that end, a single transient voltage spikehas potential to damage and/or disrupt components of the powertransmitter's electrical circuitry. Additionally or alternatively,electrical noise produced by a vehicular power source, even that ofrelatively low energy, can cause significant interruption to digitalcommunications. The vehicular power input regulator 90 may be configuredfor transient voltage suppression, among other things, to protectdownstream components of the power transmitter 20B.

FIG. 8 is an exemplary plot 19 illustrating an example voltageembodiment of an input power signal 13, communicated from the inputpower source 11 to the vehicular power input regulator. It is noted thatthe plot 19 is not to scale and the voltage values are merely exemplary.The input power signal 13 is generated from a vehicular power sourcelike, for example, an alternator and/or battery of a vehicle. Due to thenature of vehicles and the various affects that components of saidvehicle may have on the voltage of the power signal 13, a plurality oftransient voltages may be applied to the connection and/or rail uponwhich the input power signal 13 propagates. As illustrated, and viewedin reference to the baseline 0 V level, the voltage of power in avehicular power connection and/or rail may have transient spikes anddips that could affect components attached to said connection and/orrail. As illustrated, such transients may be alterations to a nominalvoltage and include, but are not limited to including, voltage drops dueto a crank, load dumps drastically increasing voltage, signal noise,overvoltages from various sources, such as jump starts, reverse batteryconnections, among other things.

The vehicular power input regulator 90 is utilized by the powertransmitter 20B to substantially “flatten” the exemplary plot 19, thusproviding a constant, safe voltage in the filtered power signal providedto downstream components of the power transmitter 20. As illustrated inFIGS. 9A-E, the vehicular power input regulator 90 includes an inputprotection circuit 91, which is utilized in removing transients from theinput power signal and/or flattening the voltage of the input powersignal to a common, sustained voltage.

Turning now to FIG. 10 and with continued reference to FIGS. 9A-E,components of the input protection circuit 91 are illustrated. The inputprotection circuit 91 may include an electrostatic discharge (ESD)protection circuit 94, which is configured to prevent ESD and/ormitigate ESD entering or occurring within the power transmitter 20.“Electrostatic Discharge (ESD),” as defined herein, is the sudden flowof electricity between two electrically charged objects caused by one ormore of contact, an electrical short, and/or dielectric breakdown. ESDmay occur when differently-charged objects are brought close together orwhen the dielectric between them breaks down. Exemplary ESD protectioncircuits 94 may embody or include diodes, Transient Voltage Suppressors(TVS), Zener diodes, among other things.

The input protection circuit 91 may further include an electromagneticinterference (EMI) mitigation circuit 95. EMI, which may, alternatively,be referred to as “radio-frequency interference,” refers todisturbances, which may be, generally, unwantedly generated bycomponents of the power transmitter 20B, which may affect an electricalcircuit, and are generated by electromagnetic induction, electrostaticcoupling, and/or conduction, among other sources for EMI. Suchdisturbances may degrade the performance of the circuit, stop thecircuit from functioning and/or may violate EMI limits for commercialproducts, as provided via regulation. Both man-made and natural sourcescan generate changing electrical currents and voltages, which may causeEMI. Accordingly, the EMI mitigation circuit 95 may be included tomitigate the ill effects of EMI on components of the power transmitter20B and/or limit transmission of EMI by the power transmitter 20B. TheEMI mitigation circuit 95 may embody or include filters, RF filters,common mode chokes, ferrite beads, inductors, tuning networks, amongother things.

The input protection circuit 91 may include an overvoltage protectioncircuit 92, which is configured for protecting components and/orsubcomponents of the power transmitter 20 from overvoltages in the inputpower signal. “Overvoltage,” as defined herein, refers to when a voltagein the power transmitter 20 is raised above the upper design limit ofany component of the power transmitter 20B. Overvoltages may causedamage and/or failure in components of the power transmitter 20B.Depending on the duration of an overvoltage, an overvoltage event can bea transient, such as a spike, or may be a substantial constant and/orpermanent overvoltage, thus resulting in power surge. Exemplaryovervoltage protection circuits 92 may embody or include a crowbarprotection circuit, a Zener voltage regulator circuit, Zener diodes,bipolar transistors, voltage regulators, relays, among other knownovervoltage protection circuits.

The input protection circuit 91 may further include an undervoltageprotection circuit 93, which is configured to prevent undervoltages frombeing passed to the power conditioning system 40. “Undervoltage,” asdefined herein, occurs when the voltage of the input electrical powerdrops below intended voltage levels for operation of the powertransmitter 20B. Undervoltages may result in components failing, due toa lack of power transmitted, and/or undervoltages may cause componentsof the power transmitter 20B to draw excess current, which could resultin component failure or damage. Undervoltages may be harmful to digitallogic elements of the power transmitter 20B, as an undervoltage can puta digital logic circuit into an unknown and/or unpredictable state, maycorrupt volatile memory, such as Random Access Memory (RAM), cause amicrocontroller to perform unforeseen actions, cause unsafe conditionswithin logic circuitry, among other things. Such occurrences, whencaused by undervoltage, may cause component damage, create unsafeconditions, and/or may cause the power transmitter to stop functioning.

The undervoltage protection circuit 93 may be configured in any propermanner to prevent undervoltage, such as, but not limited to, includingextra capacitance to a circuit to provide power during a brownout,including a CPU halt mechanism, and/or switching/detecting elements toshut down the power transmitter 20B until a voltage reaches acceptablelimits. Exemplary undervoltage protection circuits 93 may embody orinclude a comparator circuit, high capacitance circuits, fail-safecircuits, timers, among other things.

Returning now to FIG. 9A, a DC/DC voltage converter 96A is included forreceiving filtered power, converting the input voltage of the filteredpower, and outputting the filtered power signal at the operating inputvoltage for the power transmitter 20B. The DC/DC voltage converter 96Amay be any element, component, and/or component configured for alteringa DC voltage of a DC power signal, which may include, but is not limitedto including one or more of a buck converter, a step-down converter, aboost converter, a transformer, an amplifier, a split-pi converter, aboost-buck converter, a push-pull converter, a full bridge converter,among other things. In some examples, the input power from the inputpower source may be about 12 V and the operating voltage for the powertransmitter 20 is about 19 V. In such examples, the DC/DC voltageconverter 96A is configured to boost or step up the voltage of the powersignal for the filtered power signal from 12 V to 19 V. In some otherexamples, the DC/DC voltage converter 96A is configured to buck or stepdown the voltage of the power signal for the filtered power signal from24 V to 19 V.

In another embodiment of the vehicular power input regulator 90Billustrated in FIG. 9B, a DC/DC input buck converter 96B is included forreceiving filtered power, bucking and/or stepping down the input voltageof the filtered power, and outputting the filtered power signal at theoperating input voltage for the power transmitter 20B. The DC/DC voltageconverter may be any element, component, and/or component configured forbucking, stepping down, and/or lowering a DC voltage of a DC powersignal, which may include, but is not limited to including one or moreof a buck converter, a step-down converter, a transformer, an amplifier,a split-pi converter, a push-pull converter, a full bridge converter,among other things. In some examples, the input power from the inputpower source may be about 12 V and the operating voltage for the powertransmitter 20B is about 12 V. In such examples, the DC/DC voltageconverter 96B is configured to maintain and/or stabilize the voltage ofthe input power signal at about 12 V. In some other examples, the DC/DCvoltage converter 96B is configured to buck or step down the voltage ofthe power signal for the filtered power signal from about 24 V to about12 V.

FIG. 9C illustrates another embodiment of a vehicular power inputregulator 90C, which is included for receiving filtered power,converting the input voltage of the filtered power, and outputting thefiltered power signal at the operating input voltage for the powertransmitter 20B. The vehicular power input regulator 90C may include aDC/DC voltage converter 96C, which may be any element, component, and/orcomponent configured for altering a DC voltage of a DC power signal,which may include, but is not limited to including one or more of a buckconverter, a step-down converter, a boost converter, a transformer, anamplifier, a split-pi converter, a boost-buck converter, a push-pullconverter, a full bridge converter, among other things. In the exemplaryembodiment of FIG. 7C, the power transmitter 20B may include an inputvoltage sensor 97 which is configured to detect and/or measure the inputvoltage of the power received from the input power source 11. The inputvoltage sensor 97 then provides such voltage information to the controland communications system 26, which may then control voltage of theDC/DC input converter 96C, based on the detected input voltage. Forexample, if the input voltage is about 12 V and the operating voltage ofthe power transmitter 20B is about 19 V, the control and communicationsystem 26 may instruct the DC/DC input converter 96C to boost and/orstep up the voltage to about 19 V. In some alternative examples, if theinput voltage is about 24 V and the operating voltage of the powertransmitter 20B is about 19 V, then the control and communicationssystem 26 may be configured to buck or step down the voltage to about 19V.

FIG. 9D illustrates another embodiment of a vehicular power inputregulator 90D, which is included for receiving filtered power,converting the input voltage of the filtered power, and outputting thefiltered power signal at the operating input voltage for the powertransmitter 20B. The vehicular power input regulator 90D may include aDC/DC buck-boost converter 96D, which may be any element, component,and/or component configured for altering a DC voltage of a DC powersignal, which may include, but is not limited to including one or moreof a buck converter, a step-down converter, a boost converter, atransformer, an amplifier, a split-pi converter, a push-pull converter,a full bridge converter, among other things. In the exemplary embodimentof FIG. 7D, the buck-boost converter 96D may be configured to detectand/or measure the input voltage of the power received from the inputpower source 11 and then buck or boost the voltage, based on the desiredoperating conditions for the power transmitter 20B. For example, if theinput voltage is about 12 V and the operating voltage of the powertransmitter 20B is about 19 V, the buck-boost converter 96D may boostand/or step up the voltage to about 19 V. In some alternative examples,if the input voltage is about 24 V and the operating voltage of thepower transmitter 20 is about 19 V, then the buck-boost converter 96Dmay be configured to buck or step down the voltage to about 19 V.

In an exemplary embodiment of a vehicular power input regulator 90E, asillustrated in FIG. 9E, elements of the vehicular power input regulator90E may be integrated with the power conditioning system 40 of the powertransmitter 20B. In such examples, the voltage regulator 46 may beimplemented to embody similar functions of any of the DC/DC voltageconverters 90A-D of FIGS. 9A-D. To that end, the voltage regulator 46may be configured to convert the input voltage from the input powersource 11 to a proper operating voltage for the power transmitter 20B.

FIG. 11 is an exemplary schematic diagram 120 for an embodiment of thepower transmitters 20. In the schematic, the amplifier 42 is afull-bridge inverter 142 which drives the transmitter coil 21 and aseries capacitor C_(S). In some examples, wherein the operatingfrequency of the power transmitter 20 is in the range of about 87 kHzand about 205 kHz, the transmitter coil 21 has a self-inductance in arange of about 5 μH to about 7 μH. In some such examples, C_(S) has acapacitance in a range of about 400 nF to about 450 nF.

Based on controls configured by the control and communications system26, an input power source 112, embodying the input power source 12, isaltered to control the amount of power transferred to the power receiver30. The input voltage of the input power source 112 to the full-bridgeinverter 142 may be altered within a range of about 1 volt (V) to about19 V, to control power output. In such examples, the resolution of thevoltage of the input power source 112 may be 10 millivolts (mV) or less.In some examples, when the power transmitter 20, 120 first applies apower signal for transfer to the power receiver 30, the power signal ofthe input power source 112 has an initial input power voltage in a rangeof about 4.5 V to about 5.5 V.

The transmitter coil 21 may be of a wire-wound type, wound of, forexample, Litz wire. As defined herein, Litz wire refers to a type ofmultistrand wire or cable utilized in electronics to carry analternating current at a frequency. Litz wire is designed to reduce skineffect and proximity effect losses in conductors at frequencies up toabout 1 MHz and consists of many thin wire strands, individuallyinsulated and twisted or woven together, following a pattern. In someexamples, the Litz wire may be no. 17 American Wire Gauge (AWG) (1.15mm) type 2 Litz wire, having 105 strands of no. 40 AWG (0.08 mmdiameter), or equivalent wire. In some examples, the Litz wire used forthe transmitter coil 21 may be a bifilar Litz wire. To that end,utilizing thicker Litz wire, such as the no. 17 AWG type 2 Litz wire,utilizing bifilar Litz wire, and combinations thereof, may result in anincreased Quality Factor (Q) for the transmitter coil 21 and higher Qmay be directly related to increases in gap 17 height and/or Z-Distance.As Q is directly related to the magnitude of the magnetic field producedby the transmitter antenna 21 and, thus, with a greater magnitudemagnetic field produced, the field emanating from the transmissionantenna 21 can reach greater Z-distances and/or charge volumes, incomparison to legacy transmission coils, having lower Q designs. WhileLitz wire is described and illustrated, other equivalents and/orfunctionally similar wires may be used. Furthermore, other sizes andthicknesses of Litz wire may be used.

Turning to FIG. 12 , an exemplary diagram 121, for portraying dimensionsof the transmitter antenna 21, is illustrated. The diagram 121 is a topperspective view of the transmitter antenna 21 and shows a top face 60of the transmitter antenna 21. Note that the diagram 121 is notnecessarily to scale and is for illustrative purposes. The top face 60and the transmitter antenna 21, generally, are relatively circular inshape. As illustrated, an outer diameter d_(o) is defined as an exteriordiameter of the transmitter antenna 21. In some examples, the outerdiameter d_(o) has an outer diameter length in a range of about 40 mm toabout 50 mm. An inner diameter d_(i) is defined as the diameter of thevoid space in the interior of the transmitter antenna 21. The innerdiameter d_(i) may have an inner diameter length in a range of about 15mm to about 25 mm. The outer diameter d_(o) and the inner diameter d_(i)may be relatively concentric, with respect to one another. Thetransmitter coil 21 has a thickness t_(w), which is defined as thethickness of the wire of the coil. The thickness t_(w) may be in a rangeof about 2 mm to about 3 mm. In such examples, the transmitter coil 21may be made of Litz wire and include at least two layers, the at leasttwo layers stacked upon each other. Utilization of one or more of anincreased inner diameter d_(i), an increased outer diameter d_(o),multiple Litz wire layers for the antenna 21, specific dimensionsdisclosed herein, and/or combinations thereof, may be beneficial inachieving greater gap 17 heights and/or Z-distances. Other shapes andsizes of the transmitter antenna 21 may be selected based on theconfiguration with the selection of the shape and size of the shieldingof the transmitter coil. In the event that a desired shielding inrequired, the transmitter antenna 21 may be shaped and sized such thatthe shielding surrounds the transmitter antenna 21 in accordance with anembodiment.

Turning now to FIG. 13 , a cross-sectional view of the transmitter coil21, within the base station 11 and partially surrounded by a shielding80 of the transmitter coil 21, is illustrated. The shielding 80comprises a ferrite core and defines a cavity 82, the cavity configuredsuch that the ferrite core substantially surrounds all but the top face60 of the transmitter antenna 21 when the transmitter antenna 21 isplaced in the cavity. As used herein, “surrounds” is intended to includecovers, encircles, enclose, extend around, or otherwise provide ashielding for. “Substantially surrounds,” in this context, may take intoaccount small sections of the coil that are not covered. For example,power lines may connect the transmitter coil 21 to a power source. Thepower lines may come in via an opening in the side wall of the shielding80. The transmitter coil 21 at or near this connection may not becovered. In another example, the transmitter coil 21 may rise slightlyout of the cavity and thus the top section of the side walls may not becovered. By way of example, substantially surrounds would includecoverage of at least 50+% of that section of the transmitter antenna.However, in other examples, the shielding may provide a greater orlesser extend of coverate for one or more sides of the transmitterantenna 21.

In an embodiment, as shown in FIG. 14 , the shielding 80 surrounds atleast the entire bottom section of the transmitter antenna 21 and almostall of the side sections of the transmitter antenna 21. As used herein,the entire bottom section of the transmitter antenna 21 may include, forexample, the entire surface area of the transmitter antenna 21 or all ofthe turns of the Litz wire of the transmitter antenna 21. With respectto the side walls, as shown in FIG. 14 , the magnetic ring 84 does notextend all the way up the side wall of the transmitter antenna 61.However, as shown in other illustrations, the side wall may extend allthe way up the side wall.

In another embodiment, the shielding 80 may surround less than theentire bottom section of the transmitter antenna 61. For example,connecting wires (e.g., connecting wires 292, as best illustrated inFIGS. 15A, 15B and discussed below) may be run through an opening in thebottom of the shielding 80.

In an embodiment, as shown in FIG. 14 , the shielding 80 is an “E-Core”type shielding, wherein the cavity 82 and structural elements of theshielding 80 are configured in an E-shape configuration, when theshielding is viewed, cross-sectionally, in a side view. The E-Coreconfiguration is further illustrated in FIG. 15 , which is a perspectiveview of the shielding 80. The shielding 80 may include a magnetic core86, a magnetic backing 85, and a magnetic ring 84. The magnetic core 86is spaced inwardly from the outer edge of the magnetic backing 85 andprojects in an upward direction from the top surface of the magneticbacking 85. The magnetic core 86 and the magnetic ring 84 function tosurround the transmitter coil 21 and to direct and focus magneticfields, hence improving coupling with the receiver coil 31 of the powerreceiver 30.

In addition to covering the entire outer diameter of the transmittercoil 21, the shielding 80 may also cover the inner diameter d_(i) of thetransmitter coil 21. That is, as shown, the inner section of the E-Coreconfiguration may protrude upward through the middle of the transmittercoil 21.

In an embodiment, the cavity 82 is configured such that the shielding 80covers the entire bottom section of the transmitter coil 21 and theentire side sections of the transmitter coil 21. The top section of thetransmitter coil 21 is not covered. The bottom section of thetransmitter coil 21 is the side of the transmitter coil 21 that isopposite of the direction of the primary power transfer to the receivercoil. With a wire wound transmitter coil 21, the side section of thetransmitter coil 21 includes the side section of the outer most windingof the coil 21.

FIG. 15A is a perspective view of the transmitter coil 21 and theembodiment of the E-core shielding of FIG. 14 and FIG. 15B is anexploded perspective view of the transmitter coil 21 and the embodimentof the E-core shielding of FIG. 14 . The transmitter coil 21 ispositioned above the shielding 80, whose combination of structuralbodies, as discussed above, may include the combination of the magneticcore 86, the magnetic backing 85, and magnetic ring 84. This magneticshielding combination functions to help direct and concentrate magneticfields created by transmitter coil 21 and can also limit side effectsthat would otherwise be caused by magnetic flux passing through nearbymetal objects. In some examples, the magnetic ring defines an opening88, in which a connecting wire 292 of the transmitter coil 21 can exitthe shielding 80.

As defined herein, a “shielding material,” from which the shielding 80is formed, is a material that captures a magnetic field. An example ofwhich is a ferrite material. The ferrite shield material selected forthe shielding 80 also depends on the operating frequency, as the complexmagnetic permeability (μ=μ′−j*μ″) is frequency dependent. The materialmay be a sintered flexible ferrite sheet or a rigid shield and becomposed of varying material compositions. In some examples, the ferritematerial for the shielding 80 may include a Ni—Zn ferrite, a Mn—Znferrite, and any combinations thereof.

Returning now to FIG. 13 and with continued reference to FIGS. 14 and 15, the shielding 80 is aligned with the transmitter antenna 21 such thatthe shielding 80 substantially surrounds the transmitter antenna 21 onall sides, aside from the top face 60. In other words, the transmitterantenna 21 may be wound around the magnetic core 86 and be surrounded,on the bottom and sides, respectively, by the magnetic backing 85 andthe magnetic ring 84. As illustrated, the shielding 80, in the form ofone or both of the magnetic backing and the magnetic core, may extendbeyond the outer diameter d_(o) of the transmitter antenna 21 by ashielding extending distance d_(e). In some examples, the shieldingextending distance d_(e) may be in a range of about 5 mm to about 6 mm.The shielding 80, at the magnetic backing 85, and the transmitter coil21 are separated from one another by a separation distance d_(s), asillustrated. In some examples, the separation distance d_(s) may be in arange of about 0.1 mm and 0.5 mm.

An interface surface 70 of the base station 11 is located at aninterface gap distance d_(int) from the transmitter coil 21 and theshielding 80. The interface surface 70 is a surface on the base station11 that is configured such that when a power receiver 30 is proximate tothe interface surface 70, the power receiver 30 is capable of couplingwith the power transmitter 20, via near-field magnetic induction betweenthe transmitter antenna 21 and the receiver antenna 31, for the purposesof wireless power transfer. In some examples, the interface gap distanced_(int) maybe in a range of about 8 mm to about 10 mm. In such examples,the d_(int) is greater than the standard required Z-distance for Qi™certified wireless power transmission (3-5 mm). Accordingly, by having agreater d_(int), empty space and/or an insulator can be positionedbetween the transmission coil 21 and the interface surface 70 tomitigate heat transfer to the interface surface 70, the power receiver30, and/or the electronic device 14 during operation. Further, such agreater d_(int) allows for interface design structures in which objectson or attached to the electronic device 14 may remain attached to theelectronic device during operation. As described in greater detailbelow, design features of the interface surface 70 may be included forinteraction with such objects for aligning the power transmitter 20 andthe power receiver 30 for operation.

Returning now to FIG. 15B, an exemplary coil 221 for use as thetransmitter antenna 21 is illustrated in the exploded view of thetransmitter antenna 21 and shielding 80. The coil 221 includes one ormore bifilar Litz wires 290 for the first bifilar coil layer 261 and thesecond bifilar coil layer 262. “Bifilar,” as defined herein, refers to awire having two closely spaced, parallel threads and/or wires. Each ofthe first and second bifilar coil layers 261, 262 include N number ofturns. In some examples, each of the first and second bifilar coillayers 261, 262 include about 4.5 turns and/or the bifilar coil layers261, 262 may include a number of turns in a range of about 4 to about 5.In some examples, the one or more bifilar Litz wire 290 may be no. 17AWG (1.15 mm) type 2 Litz wire, having 105 strands of no. 40 AWG (0.08mm diameter), or equivalent wire. Utilization of multiple layers, thickLitz wire, bifilar Litz wire, and any combinations thereof, may resultin the coil 21 achieving greater Q and/or may result in increases in gap17 height and/or Z-distance between the coil 21 and a receiver coil.

FIG. 16A is a first block diagram 311A for an implementation of the basestation 11. As illustrated, the power transmitter 20 is contained withinthe base station 11. In some examples, the base station 11 includes oneor more user feedback mechanisms 300, wherein each of the one or moreuser feedback mechanisms 300 are configured for aiding a user inaligning a power receiver 30 and/or its associated electronic device 14with an active area 310 for wireless power transmission via thetransmitter coil 21, wherein the power receiver 30 is configured toacquire near field inductive power from the transmitter coil 21. The“active area” 310, as defined herein, refers to any area, volume, and/orspace proximate to the interface surface 70 wherein the powertransmitter 20 is capable of transmitting near field inductive power toa power receiver 30.

The one or more user feedback mechanisms 300 may include one or more ofa visual feedback display 302, a tactile feedback mechanism 304, anaudible feedback mechanism 306, a marking 308 on the interface surface70, any other feedback mechanisms 300, and any combinations thereof. Thevisual feedback display 302 is configured for visually indicating properalignment of the power receiver 30 with the active area 310. The visualfeedback display 302 may include, but is not limited to including, avisual screen, a light, a light emitting diode (LED), a liquid crystaldisplay (LCD) display, other visual displays, and/or any combinationsthereof. The tactile feedback mechanism 304 is configured for tactilelyindicating if the power receiver 30 is in proper alignment with theactive area 310. The tactile feedback mechanism 304 may include, but isnot limited to including, a haptic feedback device, a vibrating device,other tactile feedback mechanisms, and any combinations thereof. Theaudible feedback device 306 is configured for audibly indicating if thepower receiver 30 is in proper alignment with the active area 310. Theaudio feedback mechanism 306 may include, but is not limited toincluding, a speaker, a sound generator, a voice generator, an audiocircuit, an amplifier, other audible feedback devices, and anycombinations thereof.

The marking 308 may be any visual and/or mechanical signifier,indicating where a user of the electronic device 14 should placehis/her/their electronic device 14 on the interface surface 70, suchthat the power transmitter 20 will be in proper alignment with the powerreceiver 30 of the electronic device 14. Additionally or alternatively,the marking 308 may indicate a location of the active area 310 and/or aproper location within the active area 70. In the exemplary embodimentof the diagram 311A, the marking 308A may be a substantiallytwo-dimensional visual indicator marked on the interface surface 70. Thesubstantially two-dimensional marking 308A may include, but is notlimited to including, a printed indicator, a logo, a message indicatinga user should place the electronic device 14 upon the marking 308A, anyother substantially two-dimensional markings, and any combinationsthereof.

In an alternative embodiment in a second schematic block diagram 311Billustrated in FIG. 16B, the marking 308B is a substantiallythree-dimensional and/or mechanical marking 308B, such as, but notlimited to, an indentation and/or notch in the interface surface 70. Thethree-dimensional marking 308B may be configured to interact withmechanical feature 72 of the electronic device 14. The mechanicalfeature 72 may be any mechanical feature of the electronic device 14and/or another connected mechanical feature and/or device associatedwith the electronic device 14. Accordingly, interaction between themechanical feature 72 and the three-dimensional marking 308B may beconfigured to align the power transmitter 20 with the power receiver 30of the electronic device 14. For example, the mechanical feature 72 maybe an external protrusion located relatively proximate to the powerreceiver 30 of electronic device 14 and the marking 308B is configuredto receive the mechanical feature and, by the nature of such receipt,the power transmitter 20 and the power receiver 30 are properly alignedfor near-field inductive wireless power transfer. In some such examples,the electronic device 14 is a mobile device, such as a smart phoneand/or tablet computing device, and the mechanical feature 72 may be anexternally attached grip device configured for gripping the electronicdevice 14 when in use. In such examples, the marking 308B is configuredto receive the grip device mechanical feature 72 and enable properalignment of the power transmitter 20 and the power receiver 30 fornear-field inductive wireless power transfer while the removablemechanical feature 72 remains attached to the electronic device 14.

FIG. 17 is an exemplary, actual, simulation 400 of a magnetic fieldgenerated by a transmitter coil 21 and/or its associated powertransmitter 20 and captured by an exemplary receiver coil 31 and/or itsassociated power receiver 30, when the transmitter coil 21 and/or powertransmitter 20 are designed, manufactured, and/or implemented accordingto the teachings of this disclosure. The receiver coil 30 was as astandard Qi™ receiver coil utilized by commercial electronic devices,such as mobile phones, and the receiver coil 30 was modelled with ametal piece behind the coil, wherein the metal piece was used tosimulate a battery. The simulation shows that the magnetic fieldgenerated by the transmitter coil 20 was captured by the receiver coil30 at an extended Z-distance of 9 mm. As discussed previously, Qi™wireless transmitter coils typically operate between coil-to-coildistances of about 3 mm to about 5 mm. The shaped-magnetics of thetransmitter coil 21 have shown to favorably reshape a magnetic field sothat coil-to-coil coupling can occur at extended Z-distances, whereinthe Z-distances are extended about 2 times to about 5 times the distanceof standard Qi™ wireless power transmitters. Furthermore, theshaped-magnetics of the present application can extend coupling ofpresent day a Qi™ wireless power transmitter at a Z-distance rangingabout 5 mm to about 25 mm. Any of the E-core and/or additional oralternative custom shapes for the shielding 80, may successfully be usedto reshape the magnetic field for extended Z-distance coupling by aminimum of a 5% compared to standard present-day power transmitters. Inaddition, any of the E-core and custom shapes previously discussed, eachin conjunction with its relation to a coil to the magnetic has also mayfurther increase z-direction coupling by at least another 5%. Anembodiment comprising a structure, the structure comprising a coil and amagnetic material, wherein a gap between the coil and the magneticmaterial residing at the inner diameter of the coil comprises 2 mm,reshapes the magnetic field so that coupling increases by 5%.

FIGS. 18A and 18B illustrate a coil array 321, which may be utilized asthe transmitter antenna 21 of one or more of the power transmitters 21,the base station 11, or combinations thereof. As illustrated, the coilarray 321 may include two or more transmitter coils 322, which may beconstructed in accordance with the specifications of the transmitterantenna 21, as discussed above, regarding dimensions, materials, andcombinations thereof, as discussed with reference to FIGS. 12-15 . Whilethe exemplary coil array 321 of FIG. 18 shows three transmitter coils322, the coil array 321 is certainly not limited to having only threetransmitter coils 322. Further, as the transmitter coils 322 areillustrated in a substantially linear and/or rectangular layout, theycertainly are not limited to being in a substantially linear and/orrectangular layout; examples of other layouts include, but are notlimited to including, a substantially square layout, a substantiallytriangular layout, an asymmetric layout, among other contemplatedlayouts. Further, while the transmitter coils 322 are illustrated aslayered and/or stacked with respect to at least one coil (e.g., firstand second transmitter coils 322A, 322B are positioned or stacked abovea third transmitter coil 322C); however, it is certainly contemplatedthat the transmitter coils 322 may have other stacking or layeredarrangements or the transmitter coils 322 may be not stacked andsubstantially co-planar. Further, while the transmitter coils 322 areillustrated as substantially circular and/or ovular in shape, it iscontemplated that the transmitter coils 322 may be of any acceptableshape for wireless power transfer including, but not limited to,substantially square in shape, substantially rectangular in shape,substantially elliptically shaped, substantially polygonal in shape,among other contemplated shapes.

As shown in FIG. 18A, the transmitter coils 322A, 322B are adjacent toeach other on a first plane. In some embodiments, the outer edge of thetransmitter coils 322A, 322B may be touching or almost touching. Almosttouching may take into account a small gap. The transmitter coil 322C isin a second plane that is beneath the first plane. The center of thetransmitter coil 322C, as shown in FIG. 18A, is positioned between theadjacent transmitter coils 322A, 322B in the second plane. The firstplane is different than the second plane. The first plane is above thesecond plane in the direction of wireless power transmission. It ispossible that the first and second plane may be reversed and the secondplane is above the second plane in the direction of wireless powertransmission. In some embodiments, the center of the transmitter coil322C may be offset from the position between the adjacent transmittercoils 322A, 322B. For example, in an embodiment, the center of thetransmitter coil 322C may be shifted to align with the center of thetransmitter coil 322B or 322A.

As illustrated, the coil array 321 includes a shielding 380. Theshielding 380 comprises a ferrite core and defines a cavity 382, thecavity 382 configured such that the ferrite core substantially surroundsall but the top faces of each of the transmitter coils 322, similar tothe shielding 80 discussed above. As illustrated, the shielding 380surrounds at least the entire bottom section of the transmitter coils322 and almost all of the side sections of the transmitter coils 322.

While not necessarily an “E-Core” shielding, the shielding 380, which isillustrated absent the transmitter coils 322 in FIG. 18C, is configuredto functionally replicate the shielding 80, but for multiple coils.Thus, while not maintaining the substantially E-shaped cross section,the configuration and location of structural members of the shielding380 are configured to substantially surround the transmitter coils 322,similarly to how the E-Core shielding 80 substantially surrounds asingle transmitter antenna 21. The shielding 380 may include a magneticcores 386, a magnetic backing 385, and a magnetic wall 384. The magneticcores 386 are spaced inwardly from the outer edge of the magneticbacking 385 and projects in an upward direction from the top surface ofthe magnetic backing 385. The magnetic cores 386 and the magnetic ring384 function to surround the transmitter coils 322 and to direct andfocus magnetic fields, hence improving coupling with the receiver coil31 of the power receiver 30.

As viewed in FIG. 18C, the cavity 382 is configured such that theshielding 380 covers the entire bottom section of the transmitter coils322 (with, for example, the magnetic backing 385) and the entire sidesections of the transmitter coils 322 (with, for example, the magneticwall 384). The top section of the transmitter coils 322 are not covered.The bottom section of the transmitter coils 322 is the side of thetransmitter coils 322 that is opposite of the direction of the primarypower transfer to the receiver antenna 31 (e.g., an opposite side to atop face of the coil 322). With a wire wound transmitter coils 322, theside section of the transmitter coils 322 includes the side section ofthe outer most windings of the transmitter coils 322.

The transmitter coils 322 are positioned above the shielding 380, whosecombination of structural bodies, as discussed above, may include thecombination of the magnetic cores 386, the magnetic backing 385, andmagnetic ring 384. This magnetic shielding combination functions to helpdirect and concentrate magnetic fields created by transmitter coils 322and can also limit side effects that would otherwise be caused bymagnetic flux passing through nearby metal objects. In some examples,the magnetic ring defines one or more opening(s) 388, in which aconnecting wire 389 of each transmitter coils 322 can exit the shielding380.

In addition to substantially surrounding the outer diameter of thetransmitter coils 322, the shielding 380 may also cover portions of theinner areas associated with the transmitter coils 322. That is, asshown, the inner section of the shielding 380 configuration may protrudeupward through the middle of each of the transmitter coils 322. In theinstant example, the three magnetic cores 386A, 386B, and 386C may havediffering shapes based on the layout/configuration of the coil array321. Accordingly, such differing shapes are each configured to fill agap between open space between elements of each of the transmitter coils322, such that an area on the interior of the innermost turn of atransmitter coil 322 is substantially filled with one or more of some ofanother transmitter coil 322 and a magnetic core 386. Note, that theshape of the magnetic cores 386A-C are merely exemplary and the magneticcores 386 can be any shape such that they substantially fill a void inthe interior of a transmitter coil 322.

Turning now to FIGS. 19A-C, example embodiments of a wireless powertransmitter 320 are illustrated, such power transmitters 320 may includelike or similar elements to those of the power transmitter 20, such as,but not limited to, the control and communications system 26, the powerconditioning system 40, the sensing system 50, the vehicular power inputregulator 90, and any components thereof. The example embodiments of thepower transmitter 320 may include the coil array 321 as the transmitterantenna 21. The illustrated embodiments of FIG. 19 show a perspectiveview of a housing 370, within which the coil array 321, its associatedshield 380, and, optionally, one or more components of the powertransmitter 320 reside. The housing may include a mechanical feature372, upon which or within which a removable front plate 500 (see: FIGS.20A-C) may be placed. The removable front plate 500 is configured to bemechanically connected to the housing 370, via the mechanical feature372, during use. The mechanical feature 372 may be any surface, inlay,groove, opening, etc., within which or upon which the removable frontplate 500 may mechanically connect and/or mechanically align with thehousing 370, when the power transmitter 320 is configured to utilizefeatures associated with the removable front plate 500.

Turning now to FIGS. 20A-C and with continued reference to FIGS. 19A-C,embodiments of the mechanical front plate 500 are illustrated, showing amechanical body 502 and a magnetic connector 510, wherein the magneticconnector resides either within or affixed to the mechanical body 502.The magnetic connector 510 is configured for connection with acorresponding receiver magnetic connector 530 (FIGS. 22, 24 ), such thatthe magnetic connection between the magnetic connector 510 and thereceiver magnetic connector 530 may provide for or enhance one or moreof mechanical alignment between a receiver antenna 31 and a transmitterantenna 321, 21, proper positioning of the electronic device 14 relativeto the housing 370 for wireless power transfer, among other mechanicaland/or alignment functions. Examples of such magnetic connections may bemagnets or magnet arrays that exist in mobile devices for alignment withproprietary and/or compliant power transmitters. The magneticconnector(s) 510, 530 may, individually, be a magnet having a singlepolarity (north “N” or south “S”) or the magnetic connector(s) 510, 530may include one or more portions having alternating or otherwise mixedpolarities, configured for connection to an inverse connector 510, 530.

To that end, FIGS. 21A-B show top views for embodiments of a magneticarray for the magnetic connector 510A and FIGS. 22A-B show top views ofembodiments of a magnetic array for the receiver magnetic connector 530.FIG. 21A shows a first magnetic connector 510A, having first and secondmagnetic portions 511A, 512A, each having a different polarity (e.g.,the first magnetic portion 511A has a north “N” polarity and the secondmagnetic portion 512A has a south “S” polarity). FIG. 22A shows a firstreceiver magnetic connector 530A, configured to magnetically connectwith the first magnetic connector 510A, which has first and secondreceiver magnetic portions 531A, 532A (e.g., the first receiver magneticportion 531A has a south “S” polarity and the second magnetic portion532A has a north “N” polarity). Thus, in use for mechanical connectionand/or physical alignment, the first magnetic portion 511A may attractthe first receiver magnetic portion 531A, due to their inverse polarity,and the second magnetic portion 512A may attract the second receivermagnetic portion 532A.

Similarly, FIG. 21B is an embodiment of a second magnetic connector 510Bhaving a plurality of first magnetic portions 511A, each having a north“N” polarity, and a plurality of second magnetic portions 512B, eachhaving a south “S” polarity.” FIG. 22B is an embodiment of a secondreceiver magnetic connector 530B, having a first plurality of receivermagnetic portions 530B, each having a south “S” polarity, and a secondplurality of receiver magnetic portions 531B, each having a north “N”polarity. Each of the first plurality of magnetic portions 511B, of Npolarity, are configured to attract one of the first plurality ofreceiver magnetic portions 531B, of S polarity. Similarly, each of thesecond plurality of magnetic portions 512B, having a S polarity, isconfigured to attract one of the second plurality of receiver magneticportions 532B, having an N polarity. Thus, by using a specificarrangement of magnetic portions 511B, 512B and a similarly configuredarrangement of receiver magnetic portions 531B, 532B, the magneticconnection between a power receiver 30 and the power transmitter 320and/or associated removable front plate 500 may be configured forspecific use with said power receiver 30.

Returning now to FIGS. 19 , each of the power transmitters 320 mayinclude a sensor 374, 376, 378, that is configured as a detection sensorfor detecting presence of the removable front plate 500. As will bediscussed in more detail below, example sensors 374, 376, 378 determinepresence of the removable front plate 500 and subsequently provideinformation of presence of the removable front plate 500 to alteroperating conditions of one or more components of the power transmitter320. For example, presence of the removable front plate 500 may causethe power transmitter 320 to alter tuning at the tuning system 24, toadjust to an operating frequency for a power transmitter 30 having thereceiver magnetic connector 530. Additionally or alternatively,information of presence of the removable front plate 500 may be used inselecting one or more coils 322 of the antenna 321, for operation inwireless power transfer to a power receiver 30. Further still,information of presence of the removable front plate 500 may be used indetermining or controlling power input to one or more coils 322 of theantenna 321.

Referring now to FIGS. 19A, 20A, 23A and 24A, in an embodiment of thepresent disclosure, the detection sensor of the power transmitter 320may be a physical detection device 374 associated with the housing 370A.The physical detection device 374 determines physical presence of theremovable front plate 500A, when the removable front plate 500A isplaced proximate to, within, and/or attached to the mechanical feature372. Thus, the physical detection device 374 may be, for example, aphysical switch which is depressed or otherwise moved to an “on”position when the removable front plate 500A is positioned, relative tothe mechanical feature 372, for use with the housing 370A and the powertransmitter 320. As illustrated best in FIGS. 23A, 24A, when theremovable front plate 500A is positioned proximate to the mechanicalfeature 372, the mechanical front plate 500 presses or otherwise is incontact with the physical switch 374.

Turning now to FIGS. 19B, 20B, 23B, and 24B, in another embodiment ofthe present disclosure, the detection sensor of the power transmitter320 may be an electronic detection device 376 associated with thehousing 370B. The electronic detection device 376 detects a signaland/or other electrical characteristic associated with the removablefront plate 500B. In such examples, the removable front plate 500B mayinclude a tag 576, configured to emit a signal that is detectable by thepower transmitter 320, via the electronic detection device 376. Forexample, the tag 576 may be a Near Field Communications (NFC) tagconfigured to emit a signal indicating presence of the removable frontplate 500B, when the tag 576 is within range of the electronic detectiondevice 376. In such examples, the electronic detection device 376 may bean NFC poller, configured to detect NFC tags and, when the removablefront plate 500B is positioned proximate to the mechanical feature 372,the tag 576 will be in detectable range for the electronic detectiondevice 376.

In another embodiment, the detection sensor of the housing 370C and/orpower transmitter 320 may be configured to detect a particular magneticfield associated with the removable front plate. As best illustrated inFIGS. 19C, 20C, 23C, 24C, a magnetic sensor 378 may be included as thedetection sensor. The magnetic sensor 378 may, in some examples, be aHall Effect sensor configured to detect a specific magnetism and/or aspecific range of magnetism. In some examples, the magnetic sensor isconfigured to detect at least one magnet associated with the removablefront plate 500C. In some such examples, the magnetic sensor 378 may beconfigured to detect one or more portions of the magnetic connector 510.Alternatively, the magnetic sensor 378 may be configured to detect analternative magnet or magnetism unassociated with the magnetic connector510.

Referring now to FIGS. 25A, 25B, in some examples, the detection sensoris configured to provide information of presence of the removable frontplate 500, such that the power transmitter 320 then controls power inputto one or more of the at least one coil 322. As illustrated, informationfrom the sensor 374, 376, 378 will be provided to the control andcommunications system 26, which will then use such information toinstruct the power conditioning system 40 to provide the power signal(s)to at least one of the coils 322A, 322B, 322C. In some examples, theremovable front plate 500 and/or the magnetic connector 510 may beconfigured to align a power receiver 30 with a center coil (e.g., coil322B) of the transmitter antenna 321; thus, when the removable frontplate 500 is sensed by the power transmitter 320, the power conditioningsystem 40 will be configured to only power said center coil (e.g., coil322B, as illustrated in FIG. 25B). It is to be noted, that while thecoils 322 are all illustrated as being powered by or otherwiseoperatively associated with a single power conditioning system 40, it iscertainly contemplated that each of the coils 322 may be powered by orotherwise operatively associated with independent circuitry (e.g.,driver circuits, amplifiers, among other power electronics).

FIG. 26 is a configuration of the power transmitter 320, whereininformation provided by the detection sensor 374, 376, 378 is utilizedby the power transmitter 320 to selectively tune the transmitter antenna321 based on the presence of the removable front plate 500. To that end,the power transmitter 320 may include a tuning system 324, which mayinclude or embody like components and/or functions to that of the tuningsystem 24, discussed above. In such examples, the tuning system may beconfigured to selectively tune the transmitter antenna 321 to operate ata first operating frequency (“TUNING A”) and a second operatingfrequency (“TUNING B”), based on the presence, or lack thereof, of theremovable front plate 500. In an example, the first operating frequencymay be associated with a lack of presence of the removable front plate500 and may be in a range of about 85 kHz to about 205 kHz. In someexamples, the second operating frequency may be associated with theremovable front plate 500 being present, relative to the mechanicalfeature 372, and may be in a range of about 127 kHz to about 360 kHz.

By including the removable front plate 500 and magnetic connector 510with the power transmitter 320, the power transmitter 320 may be amodular and/or more adaptable wireless power transmitter that can beused with more devices having differing power receiver systems. To thatend, the inclusion of such a removable front plate may allow for a powertransmitter 20, 320 to be compatible with a standard line of powerreceivers (e.g., Qi Certified power receivers), while also allowingoptimization for other power receivers that may be differing with thestandard line of power receivers—such as those that include magneticconnectors associated with their host devices.

As is discussed above, the transmitter coils 21, 321, power transmitters20, power transmitter circuits 320, and/or base stations 11, disclosedherein, may achieve great advancements in Z-distance and/or gap 17height, when compared to legacy, low-frequency (e.g., in a range ofabout 87 kHz to about 205 kHz) transmission coils, power transmitters,and/or base stations. To that end, an extended Z-distance not onlyexpands a linear distance, within which a receiver may be placed andproperly coupled with a transmitter, but an extended Z-distance expandsa three-dimensional charging and/or operational volume (“chargevolume”), within which a receiver may receive wireless power signalsfrom a transmitter. For the following example, the discussion fixeslateral spatial freedom (X and Y distances) for the receiver coil,positioned relative to the transmitter coil, as a control variable.Accordingly, for discussion purposes only, one assumes that the X and Ydistances for the base stations 11, power transmitters 20, circuits 320,and/or transmitter coils 21, 321 are substantially similar to the X andY distances for the legacy system(s). However, it is certainlycontemplated that the inventions disclosed herein may increase one orboth of the X-distance and Y-distance. Furthermore, while the instantexample uses the exemplary range of 8-10 mm for the Z-distance of thebase stations 11, power transmitters 20, circuits 320, and/ortransmitter coils 21, 321 it is certainly contemplated and experimentalresults have shown that the base stations 11, power transmitters 20,circuits 320, and/or transmitter coils 21. 321 are certainly capable ofachieving Z-distances having a greater length than about 10 mm, such as,but not limited to, up to 15 mm and/or up to 30 mm. Accordingly, thefollowing table is merely exemplary and for illustration that theexpanded Z-distances, achieved by the base stations 11, powertransmitters 20, 320, and/or transmitter coils 21, 331 have noticeable,useful, and beneficial impact on a charge volume associated with one ormore of the base stations 11, power transmitters 20, 320, and/ortransmitter coils 21, 321.

Spatial Freedom Comparison Z- Z- Charge Charge X- Y- dist dist Vol. Vol.dist dist (min) (max) (min) (max) Legacy 5 mm 5 mm  3 mm  5 mm  75 mm³125 mm³ 11, 20, 21 5 mm 5 mm  8 mm 10 mm 200 mm³ 250 mm³ (8-10 mm. ver.)11, 20, 21 5 mm 5 mm 10 mm 15 mm 250 mm³ 375 mm³ (15 mm. ver.) 11, 20,21 5 mm 5 mm 15 mm 30 mm 375 mm³ 750 mm³ (30 mm. ver.)Thus, by utilizing the base stations 11, power transmitters 20, 320,and/or transmitter coils 21, 321, the effective charge volume mayincrease by more than 100 percent, when compared to legacy,low-frequency wireless power transmitters. Accordingly, the basestations 11, power transmitters 20, 320, and/or transmitter coils 21,321 may achieve large Z-distances, gap heights, and/or charge volumesthat were not possible with legacy low frequency, but thought onlypossible in lower power, high frequency (e.g., above about 2 Mhz)wireless power transfer systems.

As used herein, the phrase “at least one of” preceding a series ofitems, with the term “and” or “or” to separate any of the items,modifies the list as a whole, rather than each member of the list (i.e.,each item). The phrase “at least one of” does not require selection ofat least one of each item listed; rather, the phrase allows a meaningthat includes at least one of any one of the items, and/or at least oneof any combination of the items, and/or at least one of each of theitems. By way of example, the phrases “at least one of A, B, and C” or“at least one of A, B, or C” each refer to only A, only B, or only C;any combination of A, B, and C; and/or at least one of each of A, B, andC.

The predicate words “configured to”, “operable to”, and “programmed to”do not imply any particular tangible or intangible modification of asubject, but, rather, are intended to be used interchangeably. In one ormore embodiments, a processor configured to monitor and control anoperation or a component may also mean the processor being programmed tomonitor and control the operation or the processor being operable tomonitor and control the operation. Likewise, a processor configured toexecute code can be construed as a processor programmed to execute codeor operable to execute code.

A phrase such as “an aspect” does not imply that such aspect isessential to the subject technology or that such aspect applies to allconfigurations of the subject technology. A disclosure relating to anaspect may apply to all configurations, or one or more configurations.An aspect may provide one or more examples of the disclosure. A phrasesuch as an “aspect” may refer to one or more aspects and vice versa. Aphrase such as an “embodiment” does not imply that such embodiment isessential to the subject technology or that such embodiment applies toall configurations of the subject technology. A disclosure relating toan embodiment may apply to all embodiments, or one or more embodiments.An embodiment may provide one or more examples of the disclosure. Aphrase such an “embodiment” may refer to one or more embodiments andvice versa. A phrase such as a “configuration” does not imply that suchconfiguration is essential to the subject technology or that suchconfiguration applies to all configurations of the subject technology. Adisclosure relating to a configuration may apply to all configurations,or one or more configurations. A configuration may provide one or moreexamples of the disclosure. A phrase such as a “configuration” may referto one or more configurations and vice versa.

The word “exemplary” is used herein to mean “serving as an example,instance, or illustration.” Any embodiment described herein as“exemplary” or as an “example” is not necessarily to be construed aspreferred or advantageous over other embodiments. Furthermore, to theextent that the term “include,” “have,” or the like is used in thedescription or the claims, such term is intended to be inclusive in amanner similar to the term “comprise” as “comprise” is interpreted whenemployed as a transitional word in a claim. Furthermore, to the extentthat the term “include,” “have,” or the like is used in the descriptionor the claims, such term is intended to be inclusive in a manner similarto the term “comprise” as “comprise” is interpreted when employed as atransitional word in a claim.

All structural and functional equivalents to the elements of the variousaspects described throughout this disclosure that are known or latercome to be known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe claims. Moreover, nothing disclosed herein is intended to bededicated to the public regardless of whether such disclosure isexplicitly recited in the claims. No claim element is to be construedunder the provisions of 35 U.S.C. § 112, sixth paragraph, unless theelement is expressly recited using the phrase “means for” or, in thecase of a method claim, the element is recited using the phrase “stepfor.”

Reference to an element in the singular is not intended to mean “one andonly one” unless specifically so stated, but rather “one or more.”Unless specifically stated otherwise, the term “some” refers to one ormore. Pronouns in the masculine (e.g., his) include the feminine andneuter gender (e.g., her and its) and vice versa. Headings andsubheadings, if any, are used for convenience only and do not limit thesubject disclosure.

While this specification contains many specifics, these should not beconstrued as limitations on the scope of what may be claimed, but ratheras descriptions of particular implementations of the subject matter.Certain features that are described in this specification in the contextof separate embodiments can also be implemented in combination in asingle embodiment. Conversely, various features that are described inthe context of a single embodiment can also be implemented in multipleembodiments separately or in any suitable sub-combination. Moreover,although features may be described above as acting in certaincombinations and even initially claimed as such, one or more featuresfrom a claimed combination can in some cases be excised from thecombination, and the claimed combination may be directed to a subcombination or variation of a sub combination.

What is claimed is:
 1. A power transmitter for wireless power transferat an operating frequency selected from a range of about 87 kilohertz(kHz) to about 360 kHz, the power transmitter comprising: a control andcommunications unit; a vehicular power input regulator configured forreceiving input power and filtering the input power to a filtered inputpower, the vehicular power input regulator including an input protectioncircuit, and a DC/DC voltage converter; an inverter circuit receivingthe filtered input power and converting the filtered input power to apower signal; at least one coil configured to transmit the power signalto a power receiver, the at least one coil formed of wound Litz wire andincluding at least one layer, the at least one coil having at least atop face; a shielding comprising a ferrite core and defining a cavity,the cavity configured such that the ferrite core substantially surroundsall but the top face of the coil; a housing configured to house, atleast in part, one or more of the control and communications unit, theinvertor circuit, the at least one coil, the shielding, or combinationsthereof; and a removable front plate configured to mechanically connectto the housing, the removable front plate including at least one magnet,the at least one magnet configured to attract a receiver magnet when thepower receiver is proximate to the removable front plate.
 2. The powertransmitter of claim 1, further comprising a detection sensor, thedetection sensor configured to determine if the removable front plate ismechanically connected to the housing.
 3. The power transmitter of claim2, wherein the detection sensor is configured to provide information ofpresence of the removable front plate to control power input to one ormore of the at least one coil.
 4. The power transmitter of claim 3,wherein the at least one coil includes a first coil and a second coil,the first coil being the one of the at least one coil that is in closestproximity to the at least one magnet, when the removable front plate ismechanically connected to the housing, and wherein, if the removablefront plate is mechanically connected to the housing, the invertercircuit is configured to provide the power signal to the first coil. 5.The power transmitter of claim 2, further comprising a tuning system,the tuning system configured to selectively tune the at least one coilto operate at a first operating frequency and a second operatingfrequency, and wherein the tuning system is configured to switch betweenthe first and second operating frequencies in response to presence ofthe removable front plate.
 6. The power transmitter of claim 5, whereinthe first operating frequency is in a range of about 85 kHz to about 205kHz and the second operating frequency is in a range of about 127 kHz toabout 360 kHz.
 7. The power transmitter of claim 2, wherein thedetection sensor is a physical switch, the physical switch operativelyassociated with the housing and configured to generate informationindicative of presence of the removable front plate, when the removablefront plate contacts the physical switch.
 8. The power transmitter ofclaim 2, wherein the detection sensor is a magnetic sensor configured todetect a particular magnetic field associated with the removable frontplate.
 9. The power transmitter of claim 8, wherein the magnetic sensoris a hall effect sensor.
 10. The power transmitter of claim 8, whereinthe magnetic sensor is configured to detect the at least one magnet ofthe removable front plate.
 11. The power transmitter of claim 1, whereinthe at least one magnet includes a plurality of magnetic portions, theplurality of magnetic portions including a first north polarity portionand a first south polarity portion.
 12. The power transmitter of claim11, wherein the first north polarity portion is positioned adjacent tothe first south polarity portion.
 13. The power transmitter of claim 12,wherein the plurality of magnetic portions further includes a secondnorth polarity portion and the second north polarity portion ispositioned adjacent to the first south polarity portion.
 14. The powertransmitter of claim 11, wherein the receiver magnet includes a secondnorth polarity portion and a second south polarity portion, and whereinthe first north polarity portion is configured to attract the secondsouth polarity portion and the first south polarity portion isconfigured to attract the second north polarity portion, when the powerreceiver is proximate to the removable front plate.
 15. A base stationfor a wireless power transfer system at an operating frequency selectedfrom a range of about 87 kilohertz (kHz) to about 205 kHz, the basesystem comprising: an interface surface; a control and communicationsunit; a vehicular power input regulator configured for receiving inputpower and filtering the input power to a filtered input power, thevehicular power input regulator including an input protection circuit,and a DC/DC voltage converter; an inverter circuit receiving thefiltered input power and converting the filtered input power to a powersignal; at least one coil configured to transmit the power signal to apower receiver, the at least one coil formed of wound Litz wire andincluding at least one layer, the at least one coil having at least atop face; a shielding comprising a ferrite core and defining a cavity,the cavity configured such that the ferrite core substantially surroundsall but the top face of the coil; a housing configured to house, atleast in part, one or more of the control and communications unit, theinvertor circuit, the at least one coil, the shielding, or combinationsthereof; a removable front plate configured to mechanically connect tothe housing, the removable front plate including at least one magnet,the at least one magnet configured to attract a receiver magnet when thepower receiver is proximate to the removable front plate.
 16. The basestation of claim 15, wherein the input protection circuit includes anovervoltage protection circuit.
 17. The base station of claim 15,wherein the input protection circuit includes an undervoltage protectioncircuit.
 18. The base station of claim 15, wherein the input protectioncircuit includes an electrostatic discharge protection circuit.
 19. Thebase station of claim 15, wherein the input protection circuit includesan electromagnetic interference mitigation circuit.
 20. The base stationof claim 15, further comprising a detection sensor, the detection sensorconfigured to determine if the removable front plate is mechanicallyconnected to the housing.